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• MULTYCHANEL ADAPTIVE PHASE LOCK LOOP SYSTEM FOR GNSS RECEIVER

  А. А. Cherkasova, А. Y. Shatilov

  2025-04-27

  Abstract ▼

  Satellite navigation equipment often operates under conditions of a priori uncertainty of the parameters
  of the mutual dynamics between the transmitter and the consumer and the signal-to-noise ratio of the
  received signals of satellite radio navigation systems. Classical Bayesian algorithms for Phase lock loop
  system require a priori knowledge about the parameters of the phase process dynamics and the signal-tonoise
  ratio (SNR) of the received signals. As a result, the operation of such algorithms under conditions
  other than that a priori specified is not optimal to the criterion of minimum error variance. Moreover, a
  sudden change in the signal-to-noise ratio or dynamics can lead to a tracking failure in such a system.
  The purpose of this work is to develop an optimal phase tracking system that is adaptive to the dynamics
  of the phase process and the signal-to-noise ratio in order to maintain phase tracking in the widest possible
  range of operating conditions while tracking global navigation satellite system signal. An adaptive
  multichannel phase lock loop system has been synthesized as a result of formulation and solution of signal
  processing problem in terms of the statistical synthesis theory. Adaptivity to the changing power of the
  received signal is achieved by including the signal-to-noise ratio [dBHz] in the vector of estimated filter
  parameters. Adaptability to the intensity of the phase change dynamics is achieved through the use of a
  multi-channel filtration system. Statistical modeling of an adaptive multichannel phase lock loop tracking
  system with a complex algorithm for tracking the code delay of the signal of satellite radio navigation
  systems has been carried out. The values of the sensitivity of phase tracking under various dynamic conditions
  are determined. The adaptive multichannel phase lock loop system is able to withstand an signal-tonoise
  ratio jump from 50 to 10 dBHz and back without loss of phase tracking in low dynamics conditions
  (only the drift of the reference quartz oscillator). The AMPLL system is able to withstand abrupt transitions
  of dynamics between low and high (the sinusoidal acceleration 10g and sinusoidal jerk 10 g/s) without
  loss of phase tracking under the 24 dBHz signal-to-noise ratio. Thus, in real conditions, when the dynamics
  of the GNSS receiver and the SNRs of the received signals change in an unpredictable way, the
  AMPLL system keep tracking in a much wider range of conditions than the non-adaptive PLL

• DEVELOPMENT AND RESEARCH OF THE EQUALIZER CONFIGURATION TO INCREASE NOISE IMMUNITY IN DECAMETER RADIO LINES

  А. I. Rybakov

  212-227

  2025-10-01

  Abstract ▼

  The problem of increasing the noise immunity of decameter radio lines (DRL) in modern domestic radio communication systems, including short-wave (SW) communication, remains significant and in demand, despite the existence of numerous classical studies. The decameter radio communication systems have been chosen as the object of our analysis. Specifically, the R-016 system, which is used as a prototype, faces limitations such as its frequency range, which affects its effectiveness in conditions of variable ionospheric characteristics that negatively impact the signal level. Signal processing issues in prototypes can lead to bit errors reaching a bit error rate (BER) of 10^-3, even in the absence of significant interference. The main objective of the study is to evaluate the impact of various factors, such as changing the length of the preamble and implementing adaptive filters, on the noise immunity of systems. The analysis of the results indicates that increasing the length of the preamble improves the noise immunity of decameter radio lines. The practical significance of the results is that they can be used to improve the noise immunity of existing DFM radio communication systems that operate in variable ionospheric conditions. This paper also discusses the scientific basis for selecting an equalizer configuration for decameter radio lines to increase communication range and improve noise immunity. The developed methods provide a scientific basis for selecting effective equalizer settings, which can lead to improved communication range. To test different equalizer configurations in a Rayleigh channel, Simulink simulation is used, which confirms the correctness of the selected parameters. Experimental validation of the decameter radio line model includes the study of various preamble lengths, and the analysis of signal-to-noise ratios (SNR) at the receiver input allows for the adaptation of these parameters. Thus, the research results show that increasing the preamble length has a positive impact on the system's noise immunity. The work focuses on the modeling and operation of DFM radio lines, and the obtained results have practical significance for the active adaptation of existing radio systems in a changing ionosphere

• THE FORMALIZED APPROACH TO SYNTHESIS OF ARCHITECTURE IN THE SYSTEM OF ADAPTIVE GROUP CONTROL OF ROBOTIC COMPLEXES IN THE CONDITIONS OF THE NONDETERMINISTIC DYNAMIC ENVIRONMENT

  V.V. Sviridov

  2022-05-26

  Abstract ▼

  The rapid development of "multi-agent systems" as an independent and multifaceted section
  of artificial intelligence attracts many researchers in various fields of activity. The pace of progress
  in the development of information technologies, distributed information systems, and computer
  technology determines the possibilities of using robotics technologies in the Armed Forces of
  the Russian Federation. The factors presented in the article authorize the need to introduce new
  intelligent technologies into the troops - autonomous robotic complexes (systems). The development
  of artificial intelligence methods makes it possible to take a new step towards changing the
  style of interaction of complexes with each other as part of a robotic system. The idea of creating
  so-called "autonomous complexes" arose, which gave rise to a new style of adaptive group management.
  Instead of interaction initiated by the user-operator through commands and direct manipulations,
  complexes are independently involved in the joint process of solving a common problem
  in a non-deterministic dynamic environment. The article proposes a formalized approach to
  the design of architectures for group interaction of autonomous robotic complexes in a system
  based on the law of open control, i.e. induced and reliable preferences of each complex for action,
  satisfying the conditions of perfect coordination of their activities, by identifying parameters at
  which the objective function is maximized in various modes of functioning of the robotic system. A
  formalized formulation of the problem of synthesis of the adaptive group control system of autonomous
  robotic complexes under conditions of a priori uncertainty is presented. The architecture of
  group interaction of complexes is adaptively built based on the conditions of the external environment
  and the internal state of the system, in which each complex of the group functions to achieve
  a common goal (solving a system problem) at the time under consideration.